1. Field of the Invention
The present invention relates to an absorption type refrigerator and particularly, to an absorption type refrigerator having a removing apparatus for removing uncondensed hydrogen gas generated in the refrigerator.
2. Description of the Related Art
Absorption type refrigerators operated in absorption refrigeration cycles are known for use as cooling systems. Also, since its advantageous features including a higher energy efficiency during the operation have been focused, a specific class of the absorption type refrigerator in which heat pumped up from the outside air by an evaporator is also utilized to carry out a heat-pump (thermodynamic) heating operation is now anticipated to meet the market demand. For example, such a type of absorption type cool/hot water supply system is proposed in Japanese Patent Publication Hei 6-97127 which can run in three different modes: a cooling mode, a heating mode by heat-pump (thermodynamic cycle) operation, and a direct flame heating mode by direct burner (boiler) operation.
The absorption type refrigerator performs an absorption refrigerating cycle operation under a highly vacuum condition, hence causing direct contact reaction to be initiated between some components of a refrigerant and the metallic materials of a refrigerant conduit and between said components and the corrosion inhibitor thus to generate a small amount of uncondensed gas such as hydrogen gas. The presence of such an uncondensed gas declines the vacuum level in the absorber or the evaporator which must be maintained in a high level of vacuum, thus lowering the efficiency of the cooling and heating operation. It is hence necessary to carry out, at predetermined intervals, a series of maintenance jobs for exhausting the uncondensed gas using an extracting means such as a vacuum pump.
Such apparatuses for exhausting the uncondensed gas generated in absorption type refrigerators are disclosed in Japanese Patent Laid-open Publication Hei 8-121911 and 5-9001. Those apparatuses are designed to transfer the uncondensed gas separated from a refrigerant to a hydrogen exhausting conduit made of a palladium pipe heated for exhausting the gas to the atmosphere using the selective permeability of palladium.
However, the absorption type refrigerators equipped with an uncondensed gas exhausting apparatus have the following disadvantages. In the absorption type refrigerator using an alcohol refrigerant such as alcohol fluoride for absorption refrigerating cycles, it is known to mix some water and the refrigerant together for minimizing corrosion to metallic materials of the refrigerant piping. In that case, water added to the refrigerant may react on aluminum of the refrigerant piping thus to generate a small amount of hydrogen gas which has to be removed. The generation of hydrogen gas is caused by both anode reaction and cathode reaction: the anode reaction is expressed as Al.fwdarw.Al.sup.3+ +3e.sup.- and Al.sup.3 +3OH.fwdarw.AlOOH.H.sub.2 O (hydration of aluminum ion (deposition of boehmite layer)), the cathode reaction as 3H+3e.fwdarw.3/2H.sub.2 (generation of hydrogen).
The conventional uncondensed gas exhausting apparatuses disclosed in the Publications are adapted for exhausting the hydrogen gas to outside of the apparatus and thus its construction to be maintained at a higher air-tightness becomes complex. Also, the water in the refrigerant is gradually decreased and its substantial amount needed for minimizing (suppressing) the corrosion will hardly be reserved. Moreover, they allow their hydrogen exhausting piping and/or a means (e.g. a sleeve member) for housing the hydrogen exhausting piping to extend out from the gas extracting body and may hence be complicated in the outer configuration or may interfere with adjacent apparatus.